The quality of education is a current topic and much discussed in the scenario of the public policies that aim to guarantee it. However, the quality of the science education being measured through assessments is still novelty among the Brazilian municipalities, so this study is about the initiative taken by the Municipal Education Secretariat of Rio de Janeiro (SME). At first, the study presents the history of the science education in Brazil from the1940s and then explores the aspects related to the history of the science education in the city of Rio de Janeiro, emphasizing the political contexts and teaching. In a supplementary way, it discusses the issue of the quality in education and the search of it by the Municipal Network of Rio de Janeiro, reporting the political actions and their theoretical frameworks. The materials available on the network in 2010 and 2011 are examined, and also the profile of the tests applied, evaluating the changes that occurred during this period, as well as the prospects of the Network for the science education. In addition, the results achieved in the schools are presented, both in the IDERio 2010 as in the science tests of the Network, perceiving the possible impacts of the infrastructure resources of the school, of the complementary activities, of the training of the teaching staff and of the IDS in the performance of schools. The conclusion is that the quality of the science education, focusing the performance on the evaluations, still leaves much to be desired. But it is noticeable the effort of SME in structuring didactically the science education, expecting the improvement in its quality.